A GTIN (Global Trade Item Number) is the barcode number that identifies a product worldwide — the UPC in North America, the EAN in Europe. Google uses it to match your product with the same item sold elsewhere. Wrong or invented GTINs cause errors and can limit how your products are shown.
What counts as a GTIN
- GTIN-12 (UPC) — common in the US and Canada.
- GTIN-13 (EAN) — common in Europe and most other countries.
- GTIN-8 — short codes for small items.
- GTIN-14 — usually for cases or multi-packs.
The last digit is a check digit calculated from the others. If it doesn’t match, the number is invalid — usually a typo or a made-up code.
When you need one
Google’s product data specification asks for the GTIN of new products that have one assigned by the manufacturer. Products without a GTIN (for example handmade or custom items, or your own brand without registered barcodes) are submitted without one — follow the specification for your product type and use the brand and MPN where they apply. Never invent a GTIN to fill the field.
Common errors and fixes
- Invalid check digit: a digit was mistyped or the code was generated randomly. Copy the barcode exactly from the packaging or the manufacturer.
- Wrong length or letters: remove spaces, dashes and letters; GTINs are digits only.
- Restricted prefixes: codes starting with 2, 98 or 99 are for in-store or coupon use, not for products sold online.
- Bought “cheap barcodes”: codes not registered to your brand may not match the brand you submit. Get barcodes from GS1 for your own brand.
- Same GTIN on different variants: each size or colour usually has its own GTIN.
Check a GTIN in seconds
Use our free GTIN checker to validate the length and check digit of any GTIN-8, 12, 13 or 14. A MerchantLion scan with your product feed checks every GTIN in the feed automatically.
Frequently asked questions
Can I use the same GTIN for different products?
No. A GTIN identifies one specific product (including its size or colour variant).
Where do I get GTINs for my own brand?
From GS1, the organisation that issues barcodes, in your country.
Official sources
MerchantLion is independent and not affiliated with Google. Google’s documentation is the authoritative source; policies change, so check it before making decisions.
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